[Immunohistochemistry for pituitary hormones and Ki-67 in growth hormone producing pituitary adenomas].
BACKGROUND
Growth hormone (GH) producing adenomas, frequently express several hormones. This condition could confer them a higher proliferative capacity. Ki-67 is a nuclear protein antigen that is a marker for proliferative activity.


OBJECTIVE
To measure the immunohistochemical hormone expression in pituitary adenomas, excised from patients with acromegaly. To determine if the plurihormonal condition of these adenomas is associated with a higher proliferative capacity, assessed through the expression of Ki-67.


METHODS
Forty one paraffin embedded surgical samples of pituitary adenomas from patients with acromegalia were studied. Immunohistochemistry for GH, prolactin (PRL), follicle stimulating hormone (FSH), luteinizing hormone (LH), thyroid stimulating hormone (TSH), adrenocorticotropin (ACTH) and for the expression of Ki-67 was carried out.


RESULTS
All samples were positive for GH. Twenty seven had positive staining for PRL, 12 had positive staining for glycoproteic hormones and 11 for PRL and one or more glycoproteic hormones. Mean staining for Ki-67 was Z.6+/-3.3%. There were no differences in the expression of this marker between mono or plurihormonal tumors. The expression was neither associated with extrasellar extension.


CONCLUSIONS
Half of GH producing pituitary adenomas are plurihormonal. There are no differences in the expression of Ki-67 between mono and plurihormonal adenomas.
Brito
Julio
J
Sección Endocrinología, Departamento de Medicina, Hospital Clínico de la Universidad de Chile, Chile.
Sáez
Lya
L
Lemp
Melchor
M
Liberman
Claudio
C
Michelsen
Harold
H
Araya
A Verónica
AV
D000172:Acromegaly / Q000503:physiopathology / Q000601:surgery; D000236:Adenoma / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000032:analysis; D000328:Adult; D000368:Aged; D005260:Female; D005640:Follicle Stimulating Hormone / Q000032:analysis; D049912:Growth Hormone-Secreting Pituitary Adenoma / Q000378:metabolism*; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis / Q000378:metabolism*; D010911:Pituitary Neoplasms / Q000378:metabolism*; D011388:Prolactin / Q000032:analysis; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D018709:Statistics, Nonparametric; D013972:Thyrotropin / Q000032:analysis
D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D018809:Proliferating Cell Nuclear Antigen; D019382:Human Growth Hormone; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin